In TDD (Time Division Duplex), if DL (DownLink) and UL (UpLink) are allocated independently between cells, for example, as shown in FIG. 1, the timing at which UL is allocated to wireless communication terminal apparatus (hereinafter simply “terminal”) A belonging to cell 1, may overlap the timing at which DL is allocated to terminal B belonging to cell 2.
In this case, terminal B in cell 2 is subject to severe interference from terminal A in cell 1 (adjacent cell), and may not be able to decode a DL signal. This is apparent especially when terminal A and terminal B are located near their cell edges.
Therefore, as shown in FIG. 2 and FIG. 3, there is a known technique of providing a frequency band in which DL and UL are allocated independently (i.e. independent allocation band) in the cell center area in a cell, and providing a frequency band in which DL and UL are allocated in a coordinated manner between adjacent cells (i.e. coordinated allocation band) in the cell periphery area not including the cell center area in the cell. By this means, it is possible to avoid interference caused between the cells shown in FIG. 1.    Non-Patent Document 1: IST-2003-507581 WINNER D2.5 V1.1 “Duplex arrangements for future broadband radio interfaces”